Nuclear Thermal Propulsion Engine System Trades for Robotic Missions

Nuclear thermal propulsion (NTP) has emerged as a promising technology for enhancing the capabilities of robotic missions in space exploration. This paper investigates and analyzes the tradeoffs and sensitivity associated with utilizing NTP systems for robotic missions to the outer planets. The engine trade results for Jupiter and Neptune rendezvous missions using expendable configuration have demonstrated that the thrust range of 12.5–15 k-lbf (55.6–66.7 kN) can enable new frontiers and flagship-class missions with minimum initial mass in low Earth orbit. The specific impulse sensitivity analysis has shown that using a 13 k-lbf (57.8 kN) engine with an [Formula: see text] as low as 850 s can enable flagship-class missions to the gas giants in a direct transfer trajectory.